Arc-lamp.



J. A. DAYLZELYL & 0. E. HARTHAN.

ARC LAMP- APPLICATION FILED PEB.11,-1904. I Patented Oct. 13, 1908. 2 SHEETS-SBEET 1.

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IFWV6TMbOYS, Witnesses: Charles EHcrr' chGn. m 5 25m. 4 James A. Dalzel I W W wi /WM J. A. DALZELL 8/: G. E. HARTHAN.

ARC LAMP. APPLICATION FILED PEB.11, 1904. 900,709. I Patented Oct. 13,1908.

I 2 SHEETSSHEET 2. Fig. 2.

v p lnvenhors, Witnesses: Cherries E.HCIY' bh0fi, Q Jamss A. Dcrlzsl I.

. UNITED STATES PATENT OFFICE.

JAMES A. DALZELL AND CHARLES E. HARTHAN, OF LYNN, MASSACHUSETTS, ASSIGNO RS TO GENERAL ELECTRIC COMPANY, A- CORPORATION OF NEW YORK.

Ana-LAMP.

Patented Oct. 13, 1 908.

Application filed February 11, 1904. Serial No. 193,095.

To all whom it may concern:

Be it known that we, JAMES A. DALZELL and Uranus E. HAnTHAN, citizens of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Arc- Lamps, of which the following is a specification.

This invention relates to are lam s, and its object is to improve certain deta s of construction, whereby the cost of the lamp is greatly decreased and its operationimproved.

One feature of the present invention is that a number of the parts of the lamp, such for instance as the clutch connecting rod, the jaw and yoke of the clutch and the metallic parts ,of the magnet spools are made from sheet-metal. Blanks of the required shape are unc'hed out and then bent tov the particu ar form desired. Prior to ourinvention most of these arts have commonly been cast I at a cost great y in excess of the cost of making them from sheet-metal. We have therefore succeeded in efiecting a considerable reduction in the cost of the lamp without impairing its strength or durability in any way.

Other features of the invention are the pro- I vision of guides for the clutch and a gas-cap having a gas-passage which may be partially or entirely closed, as desired.

The novel features of our invention will be definitely indicated in the appended claims;

the details of construction and the mode of operation will be better understood by reference to the accompanying drawings which show one embodiment of our invention and in which Figure 1 is a sectional elevation of an arc lamp equipped with our improvements, and Figs. 2 to 8 inclusive are detail views of the various parts.

In the drawings we have shown an arc lamp of the differential'type for use in series on anlalternating-current circuit in connection with constant-current transformers, but it must bejunderstood that the improvements are not limited in any way to any particular typp of lamp.

eierring to Fig. .1, 1 indicates the slotted carbon-tube or backbone which is secured at its lower end to the annular baselate 2 but insulated therefrom by the disk 0 insulating material 3. At its u per end the backbone 1 is secured to but insu ated from the lamp top 4 which carries the binding-posts 5 5, the insulatedsuspending-link 6 and the cut-out switch 7. Instead of using a drawn or cast tube in making the backbone 1, as has been the common practice heretofore, we form the backbone from a sheet-metal blank. We

have found that a slotted carbon-tube can [be made in this-way quite strong enough for the purpose and at a cost much less than those eretofore made. This reduction in the cost is greater because of the fact that the slot in the tube may be provided for in punching the blank instead of cutting it in the completed tube in a separate 0 eration. sheet-metal blank for the backbone is shown developed in Fig. 2 it is rectangular in shape except for a cut-away portion on one or both sides, which, when the blank is curled into a tube, forms the slot through which connection is made to the movable electrode.

Sus ended from the under side of the lamp top 4 y osts 8 8 but insulated therefrom are two p ates 9, one on either side of the backbone 1, from which are suspended, by

two flat U-shaped springs 10, two pairs of solenoids 11 12, the former being woundwith coarse wire and connected in series with the arc, and the latter with fine wire and in shunt to the arc. The spools on which the coils of these solenoids are wound are preferably constructed as shown on the ri ht of Fig. 1. A sheet-metal blank, referab y brass, is curled to form a tube 13 w ich is covered with insulating material, preferably b winding heavy )a ernthereon to form a tu e 16, andinsulatlng washers 17 are laced on tube 16. The heads 14 of the spoo s are then placed on theends of tube 13 and the ends of the tube are turned over to hold the heads securely, For greater rigidity, the heads may be soldered to tube 13. The heads 14 are also metal punchings circular in form and provided with integral proi'ecting ears 15- by which the spools are al tied together as shown in the drawings. If it is desired, the insulating tube 16 may be formed separately of heavy paper and placed over tuzbe 13 in e metallic parts are .well'insulated, and the cost of production is small. Each spool of the shunt magnet has a fixed laminated core The 18 suspended by ears attached to the upper v head of the spool and extending down part way through the spool. A movable core or armature 19 is provided for each pair of spools, composed of U-shaped laminations fastened together. A flat spring 20 is secured at each end to the cross-bar of each movable core, the downward flexure of the spring being limited by a fixed stop 21 depending-from the cross-bar. The connect mg rods 22 are attached to the springs 20, each extending down to a pivotal connection with one end of a rocker 23 composed of two parallel bars, one on either side of the backone 1 and pivoted to, the backbone at 24. The two armatures practically balance each other and in order to be able to adjust this balance a wei ht 25 is mounted on the rocker and provide with a clam ing screw 26 which enters a lon itudinals ot in a bar 27 attached to the roc er 23 so that the weight can be ad'usted on either side of the ivot 24.

Secure to one end of the rocker etween plates 29 of insulating material is a contact 28 connected by a flexible lead 32 to the negative binding-post 5 of the lamp and co-- operating with a spring contact 30 mounted on the insulating disk 3 to form a cut-out switch. Contact 30 is connected to a coiled resistance wire 31 wound on a metallic tube covered with insulating material, which is mounted on the base 2 of the lamp. An inverted dash-pot 33 is ivotally connected to the armature 19 of tiie series magnet 11' and coi'iperates with a stationary plunger 34 loosely attached to an arm projecting from the backbone 1.

Rigidly suspended from the base-plate 2 by posts 35 which are insulated from the base-lpllate by suitable bushings, is a gas-cap 36 w 'ch closes the top of the inner, arcinclosing globe 40 and which serves as a tripping platform for the clutch. Loosely mounted on a rod 38 extending between the two bars of the rocker 23 is a spool 41 of wood or other insulating material, to which is secured the clutch-connecting rod 39. This rod is a sheet-metal punching twisted at right anglesnear its upper end as shown in Fig. 1 and bent around the cylindrical portion of the spool 41. At its lower end rod 39 is pivotally connected to the clamp-jaw 42 of the clutch which is ivoted in ears 43 on the yoke 37 of the clutc i. Yoke 37 and jaw 42 are also formed from sheet-metal blanks, shown developed in Figsf3 and 4. The blank for the yoke is of rectangular shape with perforated projections on its ends to form the ears 43. The blank is bent to substantially hexa onal shape, as shown by the dotted lines in ig. 3, and the ears 43 are bent out parallel to each other as shown in Fig. 1. The blank for jaw 42 has wings 44 44 which are .bent down perpendicular to the body portion as indicated by the dotted lines in Fig. 4 to form the sides of the jaw and a pr0- j ecting tongue 45 which is bent under to form the tooth or engaging portion, as shown in Fig. 5. The wings 44 of the blank 42 are provided with holes for pivotally connecting the jaw to the rod 39 and yoke 37. Secured to the baseplate 2 but insulated therefrom is a sheet-metal support 46 having depending arms 48 which extend down on either side of jaw 42 and guide the clutch in its vertical movement.

The gas-cap 36 has a spiral gas-passage 49 formed in it as shown in dotted lines in Fig. 6, through which the gases from the arc pass. The entrance to this passage is through two or more holes 50 which are threaded and-in one or more of which screws 51 may be inserted to partially or entirely close the entrance to the gas-passa e. In this manner the speed of exchange 0 air for the escaping products of combustion within the inclosing globe can be regulated or adjusted to best suit the lparticular kind of electrodes which are emp yed, and the particular length of 'arc which it is desired to maintain. The

lower electrode is supported in a holder not shown in the drawings but secured to' the end of the rod 52 which is suspended from the baselate 2 and insulated from the base plate an gas-cap 36. The globe 40 is held tightly against the gas-cap 36 by a springsuspended wire bail 53 formed with a horizontal loop in which the end of the globe rests, and a vertical loop which serves as a finger-hold. The supports for the bail 53 are coiled springs 56 each held in a tubular casing 54 secured to the under side of the base-plate 2. A sheet-metal plunger 55 extends up through each spring 56 and is spread at its end to retain a washer 61 against which the end of spring 56 presses. The lower end of plunger 55' is provided with a loop which receives the end of bail 53. Another washer 62 loose on plunger 55 closes a slot in the bottom of casing 54 through which the looped end of plunger 55 is passed in assembling the parts. r

The electrical connections are as follows: From the ositive binding-post 5, connection is ma e to the series magnets 11, the shunt magnets 12 and the resistance coil 31; from the series magnets, wire 57 leads to a screw 60 extending throu h the slot in the carbon tube 1 and into a older for the u per electrode; from the lower electrode t e current flows up through rod 52 and by wire 58 to the negative binding-post 5 from the shunt magnet, wire 59 leads to the negative return wire 58; and the resistance coil 31 is connected to one contact of the cut-out switch, the other contact of which is connected by wire 32 with the negative return wire 58.

What we claim as new and desire to secure prevent lateral movement thereof.

2. In an arc lamp, a gas-cap having a gaspassage therethrough, and a plurality of openings from the under side of the cap to the passage, said openings being threaded to receive screws whereby entrance to the. gaspassa e may be partially or entirely closed.

3. is an article of manufacture, a clutch for use in an arc lamp, consisting of a yoke and a jaw pivoted thereto, said jaw having a bodjy; portion. and wings bent at right angles to t e body portion and provided with holes for pivotally connecting the jaw to the yoke 5. An electric arc lamp having an arc-inclosing bulb communicating With the air Hthrough an elongated passage, and means for adjusting the effective length of said passage.

6. In an electric arc lamp, the combination of an arc-inclosing bulb, a cap closing the end of said bulb having an opening through which the movable electrode slides, the interior of said bulb being in communication with the outer air through an elongated passage, and means cooperating with said passa e to vary the eifective length thereof.

11 witness whereof, We'have hereunto set our hands this ninth day of February, 1904.

JAMES A. DALZELL. CHARLES E. HARTHAN. Witnesses:

DUGALD McK. MoKILLoP, JOHN A. MoMANUs. 

